Effect of seed soaking treatment with growth regulators on phytohormone level and sex modification in cucumber (Cucumis sativus L.)

摘要

Field experiments were undertaken at national agricultural research centre Islamabad, Pakistan during 2004 and 2005 to study the seed soaking effects of 2-chloroethylphosphonic acid (ethrel), gibberellic acid?and maleic hydrazide (MH) on sex modification in cucumber and to find out the critical phytohormones level of endogenous hormones for lowest sex ratio. Seeds were soaked in different concentrations of growth regulators for 20 h prior to sowing. Seed soaking with?MH?at 450?mmol/L highly increased the number of pistillate flowers and fruit yield per plant and decreased the sex ratio compared to that of untreated control. The phytohormone levels of indole acetic acid (IAA) at blooming and fruiting stages were significantly higher with? MH at 450?mmol/L and had a positive significant correlation with the number of pistillate flower/plant and negative correlation with sex ratio. Fruit yield had also a positive significant correlation with endogenous IAA. Ethrel also significantly lowered the?male to female sex ratio in cucumber.